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Updated: Jun 30, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Evolution of the individual.
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA.
The American Naturalist
|July 1, 1997
Summary
This study models how cooperation evolves in multicellular organisms, showing that organism-level selection for genetic modifiers is key to overcoming internal conflict and establishing individuality.
Area of Science:
- Evolutionary biology
- Developmental biology
- Genetics
Background:
- The transition from single-celled to multicellular life represents a major evolutionary step.
- Understanding the origin of individuality requires examining the emergence of cooperation and regulation of conflict.
- Major evolutionary transitions involve changes in the units of selection.
Purpose of the Study:
- To investigate the evolutionary transition from unicellular to multicellular life.
- To analyze the origin of individuality as a case study.
- To model the emergence of cooperation and regulation of conflict in major evolutionary transitions.
Main Methods:
- Explicit genetic models of mutation and selection.
- Modeling within-organism and between-organism dynamics.
- Analyzing fitness covariance and within-organism variation.
Main Results:
- Cooperation increases when organism-level fitness covariance surpasses within-organism defection.
- Selection and mutation during development create significant within-organism variation.
- This variation drives the evolution of genetic modifiers that mediate conflict.
Conclusions:
- The evolution of genetic modifiers is crucial for increasing organism-level heritability.
- These modifiers represent the first new functions at the organism level.
- The evolution of such modifiers is a necessary component for the origin of individuality.
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